1. MARATHON OIL CORPORATION REPORTS FIRST QUARTER 2006 FINANCIAL RESULTS
HOUSTON, April 27, 2006 – Marathon Oil Corporation (NYSE: MRO) today reported first quarter 2006 net
income of $784 million, or $2.13 per diluted share. Net income in the first quarter 2005 was $324 million, or
$0.93 per diluted share. For the first quarter of 2006, net income adjusted for special items was $739 million,
or $2.01 per diluted share. For the first quarter of 2005, net income adjusted for special items was $357
million, or $1.02 per diluted share.
Earnings Highlights
1st Quarter Ended March 31
(Dollars in millions, except per diluted share data) 2006 2005
Net income adjusted for special items* $739 $357
Adjustments for special items (net of taxes):
Gain (loss) on long-term U.K. natural gas contracts 45 (33)
Net income $784 $324
Net income adjusted for special items* - per diluted share $2.01 $1.02
Net income - per diluted share $2.13 $0.93
Revenues and other income $16,638 $13,010
Weighted average shares, in thousands - diluted 368,380 348,645
* See page 6 for a discussion of net income adjusted for special items.
Key Events
Exploration and Production
• Exceeded guidance on production available for sale due to strong operating performance
• Resumed operations in Libya and achieved first crude oil liftings
• Acquired significant leasehold position in the Bakken Shale play in North Dakota and eastern Montana
• Announced two exploration/appraisal successes – the Mostarda discovery offshore Angola and the
Gudrun appraisal well offshore Norway
Refining, Marketing and Transportation
• All refinery construction projects are on schedule to meet the June 1, 2006, ultra low sulfur diesel
requirements
• Achieved significant same store gasoline sales volume growth of 3.3 percent at Speedway SuperAmerica
LLC (SSA) and increased same store merchandise sales by 10.2 percent
Integrated Gas
• Equatorial Guinea Liquefied Natural Gas (LNG) Train 1 project remains on schedule for the first shipment
in the third quarter of 2007, having achieved 73 percent completion at the end of the first quarter
Corporate

2. • Repurchased approximately $230 million of Marathon common shares as part of previously announced
$2 billion share buy back program
• Increased dividend by 21 percent to a new quarterly rate of 40 cents per share
“In the first quarter, Marathon benefited from strong operational performance in all of our business
segments,” said Clarence P. Cazalot, Jr., Marathon president and CEO. “We achieved additional exploration
success and continued to advance our major project developments safely and on time around the globe.
These projects, along with the resumption of our operations in Libya, are positioning the Company to achieve
a compounded average production growth rate of 8-11 percent between 2004 and 2008. Our downstream
operations contributed to our strong results primarily due to the favorable refining margins and higher refined
product sales volumes we experienced during the quarter. In addition, downstream results were significantly
enhanced as a result of the minority interest acquisition completed June 30, 2005.”
Segment Results
Effective January 1, 2006, Marathon revised its measure of segment income to reflect the effects of minority
interests and income taxes related to the segments. In addition, the results of activities primarily associated
with the marketing of the Company’s equity natural gas production, which have been presented as part of the
Integrated Gas segment prior to 2006, are now included in the Exploration and Production segment. Segment
income amounts for all periods presented in this release reflect these changes.
Total segment income was $804 million in first quarter 2006, compared with $430 million in first quarter
2005.
1st Quarter Ended
March 31
(Dollars in millions) 2006 2005
Segment Income
Exploration & Production (E&P)
United States $245 $177
232 157
International
Total E&P 477 334
Refining, Marketing & Transportation 319 74
8 22
Integrated Gas
Segment Income ** $804 $430
** See Preliminary Supplemental Statistics on page 8 for a reconciliation of segment income to net income as reported
under generally accepted accounting principles.
Exploration and Production
Upstream segment income totaled $477 million in first quarter 2006, compared to $334 million in first quarter
2005. The increase was primarily due to higher product prices and liquid hydrocarbon sales volumes.
Reported sales volumes during the quarter averaged 376,800 barrels of oil equivalent per day (boepd)
compared to production available for sale of 418,600 boepd. This difference was due to the timing of
international crude oil liftings in Libya, Equatorial Guinea and the United Kingdom.
Marathon's first quarter production available for sale was higher than guidance due to outstanding operational
performance. The Company’s United Kingdom operations benefited from high seasonal natural gas sales and
increased liquid hydrocarbon production resulting from a successful workover program. Marathon continues to
Marathon Oil Corporation Reports First Quarter 2006 Results page 2

3. estimate 2006 average daily production available for sale to be 365,000 to 395,000 boepd, excluding the
impact of any acquisitions or dispositions.
United States upstream income was $245 million in first quarter 2006, compared to $177 million in first
quarter 2005. The increase was primarily a result of higher product prices and liquid hydrocarbon sales
volumes. The increase in sales volumes was a result of the Gulf of Mexico Petronius facility being shut-in
during the majority of the first quarter of 2005 for hurricane related repairs.
International upstream income was $232 million in first quarter 2006, compared to $157 million in first
quarter 2005. The increase was primarily a result of higher product prices and higher liquid hydrocarbon sales
volumes due to the resumption of production in Libya and the benefit of a full quarter of the condensate
expansion project in Equatorial Guinea.
1st Quarter Ended March 31
2006 2005
Key Production Statistics
Sales
United States – Liquids (mbpd) 80.0 71.6
United States – Gas (mmcfpd) 561.2 570.3
International – Liquids (mbpd) 130.7 91.5
International – Gas (mmcfpd) 435.1 455.2
Total Sales (mboepd) 376.8 334.0
Marathon continues to advance its major projects. As of the end of the first quarter 2006, the Alvheim project
in Norway was 53 percent complete, and on target to deliver first production in the first quarter of 2007. As
part of this project, the hull modifications to the Alvheim floating production storage offloading (FPSO) vessel
have been completed and the vessel sailed from Singapore to Norway where it is undergoing topside
installation work. Alvheim development drilling is scheduled to begin in May 2006. The Neptune development
in the Gulf of Mexico was 22 percent complete through March 2006, and remains on target to deliver
production by early 2008, with development drilling scheduled to begin in May 2006.
Marathon recently completed leasehold acquisitions totaling approximately 200,000 acres in the Bakken Shale
resource play, located in the Williston Basin of North Dakota and eastern Montana. With this substantial
position in the Bakken Shale, Marathon plans to drill approximately 300 wells over the next four to five years,
with additional infill drilling likely. This program has the potential to add more than 20,000 barrels of oil
equivalent per day of production by 2012.
Offshore Norway, Marathon participated in a successful appraisal well on the Gudrun prospect. Two zones
were tested at an aggregate gross rate of more than 10,000 barrels of oil per day (bpd) and 30 million cubic
feet of natural gas per day (mmcfd). Future activities will primarily focus on evaluating various development
scenarios. Marathon holds a 28 percent non-operated working interest in Gudrun.
Offshore Angola, Marathon participated in the discovery well on the Mostarda prospect in Block 32, where the
Company holds a 30 percent working interest. This discovery is located near the previously announced
Gindungo, Canela and Gengibre discoveries. In Block 31, where the Company holds a 10 percent working
interest, Marathon participated in a successful appraisal well in the northeast part of the block, a dry hole in
the southeast portion of the block, and the Urano well reached total depth. The results of the Urano well will
be reported upon governmental approvals.
Marathon Oil Corporation Reports First Quarter 2006 Results page 3

4. Refining, Marketing and Transportation
Downstream segment income was $319 million in first quarter of 2006 compared to $74 million in first quarter
of 2005. Downstream segment income for the first quarter of 2006 benefited from the June 30, 2005,
minority interest acquisition, while the first quarter 2005 was negatively impacted by a legislated tax increase
by the State of Kentucky.
A key driver of the increase in segment income was the Company’s refining and wholesale marketing gross
margin which averaged 11.37 cents per gallon in first quarter of 2006 versus 6.85 cents in the comparable
2005 quarter. This margin improvement reflected favorable sweet/sour crude oil differentials in the first
quarter 2006 and was consistent with the relevant indicators (crack spreads) in the Midwest (Chicago) and
Gulf Coast markets. The Company’s refining and wholesale marketing gross margins in the first quarters
2006 and 2005 included pre-tax losses of $11 million and $172 million related to derivatives that are utilized
primarily to manage price risk. SSA’s gasoline and distillate gross margin averaged approximately 10.55
cents per gallon during the first quarter of 2006, essentially unchanged from the margin realized in the first
quarter 2005.
Crude oil refined during the first quarter of 2006 averaged 897,600 barrels per day (bpd), slightly lower than
during the first quarter 2005. However, total refinery throughputs totaled 1,146,800 for the first quarter
2006, approximately five percent higher than the 1,093,600 bpd during the first quarter 2005.
SSA achieved significant same store gasoline sales volume growth of 3.3 percent during the first quarter 2006
compared to the first quarter 2005. In addition, SSA increased same store merchandise sales by 10.2 percent
during the same period. This marks the 13th consecutive quarter that SSA has achieved same store
merchandise sales growth of greater than 9 percent when compared to the same quarter from the previous
year.
1st Quarter Ended March 31
2006 2005
Key Refining, Marketing & Transportation Statistics
Crude Oil Refined (mbpd) 897.6 922.2
249.2 171.4
Other Charge and Blend Stocks (mbpd)
Total Refinery Inputs (mbpd) 1,146.8 1,093.6
Refined Product Sales Volumes (mbpd) 1,416.6 1,369.7
Refining and Wholesale Marketing Gross Margin
$0.1137 $0.0685
($/gallon)
Marathon is on schedule to meet the Federal EPA regulations which require ultra low sulfur diesel fuel
production effective June 1, 2006. These modifications will complete the approximately $900 million capital
project the Company began in 2002 to comply with the Tier II gasoline and on-road diesel requirements of the
Clean Air Act that are effective as of June 1, 2006.
Integrated Gas
Integrated gas segment income was $8 million in first quarter 2006 compared to $22 million in first quarter
2005. The decrease was primarily a result of a higher provision for income taxes.
Marathon Oil Corporation Reports First Quarter 2006 Results page 4

5. The Equatorial Guinea LNG Train 1 project made continued progress during the quarter and remains on-track
to begin first shipments of LNG in the third quarter of 2007. At the end of the first quarter, the project was
approximately 73 percent complete on an engineering, procurement and construction (EPC) basis. Marathon
holds a 60 percent interest in Equatorial Guinea LNG Holdings Limited.
Corporate
In January 2006, Marathon announced a $2 billion share repurchase plan. Through the first quarter of 2006,
Marathon has repurchased approximately $230 million of its common shares. The Company expects to
repurchase shares ratably through 2007 unless market or other conditions change significantly.
The Company's board of directors has approved a seven cent, or 21 percent, per share increase in the first
quarter dividend payable on Marathon Oil Corporation Common Stock, resulting in a new quarterly dividend
rate of 40 cents per share.
Annually, the Corporation determines its income tax provision by aggregating income taxes arising from each
jurisdiction in which it operates. In interim periods, the income tax provision is determined by applying an
estimate of the Corporation’s annual effective tax rate to quarterly pre-tax earnings. This tax accounting
method can result in volatility in segment income quarter over quarter.
Special Items
Marathon has two long-term natural gas sales contracts in the United Kingdom that are accounted for as
derivative instruments. Mark-to-market changes in the valuation of these contracts must be recognized in
current period income. During the first quarter 2006, the non-cash after-tax mark-to-market gain on these
two long-term gas sales contracts related to Marathon's Brae gas production totaled $45 million. Due to the
volatility in the fair value of these contracts, Marathon consistently excludes these non-cash gains and losses
from “net income adjusted for special items.”
The Company will conduct a conference call and webcast today, April 27, 2006, at 2 p.m. EDT during which it
will discuss first quarter 2006 results. The webcast will include synchronized slides. To listen to the webcast
of the conference call and view the slides, visit the Marathon Web site at www.marathon.com. Replays of the
webcast will be available through May 11, 2006. Quarterly financial and operational information is also
provided on Marathon’s Web site at http://www.marathon.com/Investor_Center/Investor_Relations/ in the
Quarterly Investor Packet.
- xxx -
Marathon Oil Corporation Reports First Quarter 2006 Results page 5

6. In addition to net income determined in accordance with generally accepted accounting principles, Marathon
has provided supplementally “net income adjusted for special items,” a non-GAAP financial measure which
facilitates comparisons to earnings forecasts prepared by stock analysts and other third parties. Such
forecasts generally exclude the effects of items that are difficult to predict or to measure in advance and are
not directly related to Marathon's ongoing operations. Reconciliation between GAAP net income and “net
income adjusted for special items” is provided in a table on page 1. “Net income adjusted for special items”
should not be considered a substitute for net income as reported in accordance with GAAP.
Management, as well as certain investors, uses “net income adjusted for special items” to evaluate Marathon's
financial performance between periods. Management also uses “net income adjusted for special items” to
compare Marathon's performance to certain competitors.
This release contains forward-looking statements with respect to the timing and levels of the Company's
worldwide liquid hydrocarbon and natural gas and condensate production and sales, the development of the
Alvheim field, the Neptune development, anticipated future drilling activity, an LNG project in Equatorial
Guinea, and the common stock repurchase program. Some factors that could potentially affect worldwide
liquid hydrocarbon and natural gas and condensate production and sales, the development of the Alvheim field
and Neptune, and anticipated future drilling activity include pricing, supply and demand for petroleum
products, amount of capital available for exploration and development, regulatory constraints, inability or
delay in obtaining government and third-party approvals and permits, timing of commencing production from
new wells, drilling rig availability, unforeseen hazards such as weather conditions, acts of war or terrorist acts
and the governmental or military response thereto, and other geological, operating and economic
considerations. Worldwide production and sales could also be affected by the occurrence of acquisitions or
dispositions of oil and gas properties. Factors that could affect the LNG project include unforeseen problems
arising from construction, inability or delay in obtaining necessary government and third-party approvals,
unanticipated changes in market demand or supply, environmental issues, availability or construction of
sufficient LNG vessels, and unforeseen hazards such as weather conditions. The common stock repurchase
program could be affected by changes in prices of and demand for crude oil, natural gas and refined products,
actions of competitors, disruptions or interruptions of the Company’s production or refining operations due to
unforeseen hazards such as weather conditions or acts of war or terrorist acts, and other operating and
economic considerations. The foregoing factors (among others) could cause actual results to differ materially
from those set forth in the forward-looking statements. In accordance with the quot;safe harborquot; provisions of the
Private Securities Litigation Reform Act of 1995, Marathon Oil Corporation has included in its Annual Report on
Form 10-K for the year ended December 31, 2005, and subsequent Forms 8-K, cautionary language
identifying other important factors, though not necessarily all such factors, that could cause future outcomes
to differ materially from those set forth in the forward-looking statements.
Media Relations Contacts: Paul Weeditz 713-296-3910
Scott Scheffler 713-296-4102
Investor Relations Contacts: Ken Matheny 713-296-4114
Howard Thill 713-296-4140
Marathon Oil Corporation Reports First Quarter 2006 Results page 6

7. Condensed Consolidated Statements of Income (unaudited)
1st Quarter Ended
March 31
(Dollars in millions, except per share data) 2006 2005
Revenues and Other Income:
Sales and other operating revenues (including
$12,998 $9,840
consumer excise taxes)
Revenues from matching buy/sell transactions 3,206 2,809
Sales to related parties 312 283
Income from equity method investments 92 40
Net gains on disposal of assets 11 11
Other income, net 19 27
Total revenues and other income 16,638 13,010
Costs and Expenses:
Cost of revenues (excludes items below) 9,769 7,692
Purchases related to matching buy/sell transactions 3,233 2,832
Purchases from related parties 51 56
Consumer excise taxes 1,165 1,084
Depreciation, depletion and amortization 415 323
Selling, general and administrative expenses 287 260
Other taxes 149 105
Exploration expenses 71 34
Total costs and expenses 15,140 12,386
Income from Operations 1,498 624
Net interest and other financing costs 24 32
Minority interests in income (loss) of:
Marathon Petroleum Company LLC --- 70
Equatorial Guinea LNG Holdings Limited (3) (1)
Income before Income Taxes 1,477 523
Provision for income taxes 693 199
Net Income $784 $324
Net income
Per share - basic $2.15 $0.94
Per share - diluted $2.13 $0.93
Dividends paid per share $0.33 $0.28
Weighted average shares, in thousands
Basic 365,110 346,006
Diluted 368,380 348,645
Marathon Oil Corporation Reports First Quarter 2006 Results page 7

8. Preliminary Supplemental Statistics (unaudited)
1st Quarter Ended March 31
(Dollars in millions, except as noted) 2006 2005
Segment Income
Exploration & Production
United States $245 $177
232 157
International
Total E&P 477 334
Refining, Marketing & Transportation(a) 319 74
8 22
Integrated Gas
Segment Income 804 430
Items not allocated to segments, net of taxes:
Gain (loss) on long-term U.K. natural gas contracts 45 (33)
(65) (73)
Corporate and other unallocated items
Net Income $784 $324
Capital Expenditures
Exploration & Production $384 $294
Refining, Marketing & Transportation(a) 104 136
Integrated Gas(b) 94 125
17 1
Corporate
Total $599 $556
Exploration Expense (Pre-tax)
United States $28 $17
43 17
International
Total $71 $34
Operating Statistics
Net Liquid Hydrocarbon Sales (mbpd)(c)
United States 80.0 71.6
29.9 31.2
Europe
Africa 71.4 36.2
29.4 24.1
Other International
130.7 91.5
Total International
210.7 163.1
Worldwide
Net Natural Gas Sales (mmcfd)(c)(d)
United States 561.2 570.3
Europe 347.2 371.8
87.9 83.4
Africa
435.1 455.2
Total International
996.3 1,025.5
Worldwide
Total Sales (mboepd) 376.8 334.0
Marathon Oil Corporation Reports First Quarter 2006 Results page 8

9. Preliminary Supplemental Statistics (unaudited) (continued)
1st Quarter Ended March 31
2006 2005
Operating Statistics (continued)
Average Realizations (e)
Liquid Hydrocarbons ($ per net bbl)
United States $49.30 $38.47
Europe 62.14 45.34
Africa 51.35 43.23
Other International 37.39 24.79
Total International 50.68 39.10
Worldwide $50.16 $38.82
Natural Gas ($ per net mcf)
United States $6.66 $4.95
Europe 7.66 5.05
Africa 0.25 0.24
Total International 6.16 4.17
Worldwide $6.44 $4.60
Marathon Oil Corporation Reports First Quarter 2006 Results page 9

10. Preliminary Supplemental Statistics (unaudited) (continued)
1st Quarter Ended March 31
(Dollars in millions, except as noted) 2006 2005
Refinery Runs (mbpd)
Crude Oil Refined 897.6 922.2
249.2 171.4
Other Charge and Blend Stocks
Total 1,146.8 1,093.6
Refined Product Yields (mbpd)
Gasoline 645.5 576.3
Distillates 289.8 291.5
Propane 20.5 19.2
Feedstocks and Special Products 107.6 116.4
Heavy Fuel Oil 24.0 32.8
75.1 72.0
Asphalt
Total 1,162.5 1,108.2
(f)
Refined Product Sales Volumes (mbpd) 1,416.6 1,369.7
Matching buy/sell volumes included in refined
product sales volumes (mbpd) 82.6 80.3
Refining and Wholesale Marketing Gross
Margin(g)(h) $0.1137 $0.0685
Speedway SuperAmerica LLC
Number of SSA retail outlets 1,635 1,659
SSA Gasoline and Distillate Sales(i) 776 745
SSA Gasoline and Distillate Gross Margin(g) $0.1055 $0.1058
SSA Merchandise Sales $610 $560
SSA Merchandise Gross Margin $148 $143
(a)
RM&T segment income for the first quarter of 2005 is net of $67 million pre-tax minority interest in MPC. RM&T capital
expenditures includes MPC at 100 percent.
(b)
Includes Equatorial Guinea LNG Holdings at 100 percent.
(c)
Amounts represent net sales after royalties, except for Ireland where amounts are before royalties.
(d)
Includes natural gas acquired for injection and subsequent resale of 40.6 mmcfd and 20.5 mmcfd in the first quarter 2006 and
2005. Effective July 1, 2005, the methodology for allocating sales volumes between natural gas produced from the Brae
complex and third-party natural gas production was modified, resulting in an increase in volumes representing natural gas
acquired for injection and subsequent resale.
(e)
Excludes derivative gains and losses, including the effects of long-term U.K. natural gas contracts that are accounted for as
derivatives. There were no equity production hedges in the first quarters of 2006 or 2005.
(f)
Total average daily volumes of all refined product sales to wholesale, branded and retail (SSA) customers.
(g)
Dollars per gallon.
(h)
Sales revenue less cost of refinery inputs, purchased products and manufacturing expenses, including depreciation.
(i)
Millions of gallons.
Marathon Oil Corporation Reports First Quarter 2006 Results page 10